title: Evaluation of the biomechanical efficacy of limited intercarpal fusions for the treatment of scapho-lunate dissociation.
abstract: An experimental model that uses a static positioning frame, pressure-sensitive film, and a microcomputer-based videodigitizing system was used to measure the contact areas and pressures in a group of wrists in their "normal" state, after ligament sectioning, which resulted in stage III perilunate instability and then following different types of simulated carpal fusions. Compared with a normal wrist, there is an overall decrease in load in the lunate fossa and a significant increase in load in the scaphoid fossa in the wrist with stage III perilunate instability. Scaphoid-trapezium-trapezoid and scaphoid-capitate fusions transmitted almost all load through the scaphoid fossa. Scaphoid-lunate, scaphoid-lunate-capitate, and capitate-lunate fusions all distributed load more proportionately through both scaphoid and lunate fossae. The positioning of the carpal bones within a limited carpal fusion was also found to affect the load distribution in the wrist. The scaphoid-lunate, scaphoid-lunate-capitate, or capitate-lunate fusions, with attention to the relative carpal alignment within the limited fusion seem to offer more promise for treatment of perilunate instability biomechanically than the scaphoid-trapezium-trapezoid or scaphoid-capitate fusions.
authors.affiliation: Division of Orthopaedic Surgery, University of Texas Medical Branch, Galveston 77551.
authors.forename: S F
authors.initials: SF
authors.lastname: Viegas
authors.forename: R M
authors.initials: RM
authors.lastname: Patterson
authors.forename: P D
authors.initials: PD
authors.lastname: Peterson
authors.forename: D J
authors.initials: DJ
authors.lastname: Pogue
authors.forename: D K
authors.initials: DK
authors.lastname: Jenkins
authors.forename: T D
authors.initials: TD
authors.lastname: Sweo
authors.forename: J A
authors.initials: JA
authors.lastname: Hokanson
mesh_terms: D000328:Adult; D001174:Arthrodesis; D001696:Biomechanical Phenomena; D006801:Humans; D007593:Joint Instability / Q000503:physiopathology / Q000601:surgery*; D012667:Lunate Bone / Q000503:physiopathology / Q000601:surgery*; D008875:Middle Aged; D014955:Wrist Joint / Q000503:physiopathology / Q000601:surgery*